Q42.2-3CC. Suppose that after you exercise ... [FREE SOLUTION]

Chapter 42: Q42.2-3CC. (page 927)

Suppose that after you exercise regularly for several months, your resting heart rate decreases, but your cardiac output at rest is unchanged. Based on these observations, what other change in the function of your heart at rest likely occurred?

Short Answer

Expert verified

Long-term exercise results in increased stroke volume (left ventricle pumping blood in a single contraction), and this results in lowering down the resting heart rate.

Step by step solution

Exercise

The type of bodily activity that requires consistent physical effort and is designed to acquire body fitness and health benefits is called exercise.

Various benefits of exercise are better flexibility, building muscle, better appetite, improved brain function, increased energy levels, improved digestion, managing weight loss, maintaining heart function, and improved overall health.

Heart rate and cardiac output

When an electric signal travels, this causes heart contraction to push oxygen-rich blood through the living body; this speed of heart beating is called heart rate.

When the blood leaves or is pumped out of the ventricle into the aorta (body鈥檚 main artery) and pulmonary artery each minute by heart, this quantity is measured by the CO (cardiac output).

Heart functioning

Long-term exercise causes resting heart rate (number of heart contractions while a living body is at rest) to drop so that heart easily pumps more blood in fewer beats.

The cardiac output remains constant during exercise; the heart pumps and returns the same amount of blood in the same period of time. During exercise, the heart beats at a faster rate resulting in pumping more blood forcefully, and this causes greater stroke volume.